It is possible that Snoop's symptoms may be related to some of his previous health concerns but it could also be unrelated in response to eating the paper towels.
When a dog ingests foreign material like paper towels it may become stuck causing an obstruction - the symptoms that you may see when this happens include vomiting, inappetence and either diarrhea or lack of stool. It is important that Snoop be seen by your local vet to determine if there are still paper towels stuck inside causing an obstruction. The vet will be able to tell by x-rays or ultrasound. Sometimes the vet may even be able to get an idea if they could be stuck by palpating Snoop's belly.
Another way the towels can cause this problem is if the material they cleaned up have caused an issue for example if the paper towels had rich food on them that can cause pancreatitis (this is diagnosed by blood test or ultrasound). Toxins may even be an issue if the towels were used to clean up a toxic material, so best to check will the household what was on the paper towels before going to see the local vet.
It is possible that these symptoms may be related to Snoops underlying problems (increased urination, hindleg trouble, thyroid) conditions associated with these problems include diabetes, pancreatitis, and nerve damage that can effect defecation.
So to wrap this all up I suggest that you take Snoop to a local vet ASAP to be examined to see if there are any paper towels causing an obstruction. At the same time I suggest that you discuss ruling out diabetes and pancreatitis by performing blood tests and consider rechecking his thyroid level.
I realize that this all seems like a lot especially when Snoop is not doing well but I do suggest he be examined ASAP. The sooner the problem can be pin pointed by tests the better Snoop will respond to treatment and the lower the cost - if further time causes deterioration such as dehydration the more treatment he will need.
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